INSECT METAMORPHOSIS. 



347 



solution (6 g. IK, 4 g. I in 100 g. H 2 O) were daily administered 

 to the caterpillars of experiments I and 2 from August i6th, 

 and in those of experiments 3 and 4 from August 22d. Leaves 

 designed for control animals were similarly changed daily and 

 sprayed with water. All animals were kept under glass vessels. 

 The administered leaves were taken by the "iodine" caterpillars 

 as well as by those of control materials. Data referring to the 

 pupation term of these caterpillars as well as to the average 

 weight of the resulting chrysalids are recorded in Table IV. 



TABLE IV. 



DATA CONCERNING THE TERM OF PUPATION AND THE WEIGHT OF PUPJE FROM 



"IODINE" CATERPILLARS OF Pievis brassica L. 

 The terms of pupation calculated from the beginning of iodine feeding. 



It is evident that neither in the case when iodine feeding was 

 begun earlier (first and second experiment) nor in that started 

 almost a week later (third and fourth experiment) the obtained 

 results were concordant. The sign of the difference between 

 the terms in control animals and those for the experimental 

 materials was different in both cases which points to the 

 lack' of any influence of iodine feeding. On the other hand the 

 average weight of the "iodine" chrysalids was here also always 

 smaller than that of the control pupae. The total of the recorded 

 chrysalids amounted here to 37 "iodine" and 54 control speci- 

 mens. My material was therefore larger than that of Gedroyc. 

 It was nevertheless not large enough to consider the results 

 obtained as decisive, all the more as the insects weie not 

 24 



